Shear spring for vehicle suspension

ABSTRACT

A shear spring comprising a base and a V-shaped surface opposite the base adapted to mate with a corresponding V-shaped surface positioned on a side wall of a spring mount, and an elastomeric material positioned between the base and the V-shaped surface, wherein the base includes a first flange extending away from the V-shaped surface and adapted to be positioned outwardly from a first edge of a side wall of a spring module, and wherein the base includes a second flange extending away from the V-shaped surface and adapted to be positioned outwardly from a second edge of the side wall of the spring module, where the first flange and the second flange are positioned in parallel planes.

RELATED APPLICATIONS

This application is a divisional application of U.S. patent application Ser. No. 13/178,773 filed on Jul. 8, 2011 and entitled “Vehicle Suspension and Improved Method of Assembly,” which is hereby incorporated by reference in its entirety.

BACKGROUND

The present invention generally relates to vehicle suspensions. More particularly, the present invention relates to vehicle suspensions having springs. Single spring rate suspensions and variable spring rate suspensions for use in vocational or heavy haul truck applications are known. Single spring rate suspensions have a fixed spring rate that generally must be set at a level that produces a suspension with either a comfortable ride or a stiff suspension exhibiting adequate roll stability. As a result, either roll stability or ride quality is compromised in single spring rate suspensions, depending upon the selected spring rate.

Variable spring rate suspensions overcome this deficiency of single spring rate suspensions by providing for multiple spring rates during operation. As the sprung load is increased, the spring rate is correspondingly increased. An example of a variable spring rate elastomeric spring suspension for use in vocational or heavy haul truck applications is shown in U.S. Pat. No. 6,585,286, the disclosure of which is hereby incorporated herein by reference. That suspension utilizes bolster springs and auxiliary springs to achieve its variable spring rate.

The assignee of the present invention disclosed a vehicle suspension having shear springs and a load cushion with a continuously increasing spring rate in U.S. application Ser. No. 12/876,158 which is entitled “Suspension Assembly With Tie-Plate” and was filed on Sep. 5, 2010, which is a continuation-in-part of U.S. patent application Ser. No. 12/545,828 which is entitled “Tie-plate and frame hanger of a suspension assembly” and was filed Aug. 22, 2009, which is a continuation-in-part of U.S. patent application Ser. No. 12/334,195, entitled “Modular Suspension System and Components Thereof” filed on Dec. 12, 2008, and a continuation-in-part of U.S. patent application Ser. No. 12/045,069, entitled “Elastomeric Spring Vehicle Suspension” filed on Mar. 10, 2008, now U.S. Pat. No. 7,926,836, each of which is assigned to Hendrickson USA, L.L.C. This application incorporates U.S. patent application Ser. Nos. 12/545,828, 12/334,195, and 12,876,158, and U.S. Pat. No. 7,926,836 herein by reference. The present application includes improvements and advancements over the vehicle suspensions disclosed in the applications noted above.

SUMMARY

In one aspect a suspension is provided comprising a first frame attachment portion adapted for connection to a vehicle frame rail, a first spring module attached to the first frame attachment portion, said first spring module having an opening defined by a top wall, a bottom wall, and first and second side walls of said first spring module, a first spring mount positioned within the opening, a first shear spring positioned between a first side wall of the first spring mount and said first side wall of the opening of the first spring module, a second shear spring positioned between a second side wall of the first spring mount and said second side wall of the opening of the first spring module, wherein the first spring mount comprising an inboard part and an outboard part separate from the inboard part, a through-hole positioned in at least one of the inboard or inboard parts of the first spring mount adapted to allow passage of a first threaded connecting rod therethrough, wherein the first threaded connecting rod has been tightened to draw the inboard part of the first spring mount together with the outboard part of the first spring mount, and to compress the first shear spring between the first side wall of the first spring mount and the first side wall of the opening of the first spring module, and also to compress the second shear spring between the second side wall of the first spring mount and the second side wall of the opening of the first spring module.

In another aspect a suspension is provided comprising a frame attachment portion adapted for connection to a vehicle frame rail, a first spring module attached to the frame attachment portion, said first spring module having an opening defined by a top wall, a bottom wall, and first and second side walls of said first spring module, a first spring mount positioned within the opening of the first spring module, a first shear spring positioned between a first side wall of the first spring mount and said first side wall of the opening of the first spring module, a second shear spring positioned between a second side wall of the first spring mount and said second side wall of the opening of the first spring module, said first spring mount comprising an inboard part and an outboard part separate from the inboard part, a through-hole positioned in at least one of the inboard or outboard parts of the first spring mount adapted to allow passage of a first connecting rod therethrough, wherein the first connecting rod has been tightened to draw together the inboard first part of the first spring mount and the outboard second side of the first spring mount, and to compress the first shear spring between the first side wall of the first spring mount and the first side wall of the opening of the first spring module, and also to compress the second shear spring between the second side wall of the first spring mount and the second side wall of the opening of the first spring module, and a second spring module positioned adjacent to the first spring module, said second spring module having an opening defined by a top wall, a bottom wall, and first and second side walls of said second spring module, a second spring mount positioned within the opening of the second spring module, a third shear spring positioned between a first side wall of the second spring mount and said first side wall of the opening of the second spring module, a fourth shear spring positioned between a second side wall of the second spring mount and the second side wall of the opening of the second spring module, said second spring mount comprised of an inboard part and an outboard part separate from the inboard part, a through-hole positioned in at least one of the inboard or outboard parts of the second spring mount adapted to allow passage of a second connecting rod therethrough, wherein the second connecting rod has been tightened to draw together the inboard part of the second spring mount and the outboard part of the second spring mount, and to compress the third shear spring between the first side wall of the second spring mount and the first side wall of the opening of the second spring module, and to compress the fourth shear spring between the second side wall of the second spring mount and the second side wall of the opening of the second spring module.

In another aspect, a shear spring is provide comprising a base and a V-shaped surface opposite the base adapted to mate with a corresponding V-shaped surface positioned on a side wall of a spring mount, and an elastomeric material positioned between the base plate and the plate having the V-shaped surface.

In another aspect, a method of assembling a vehicle suspension is provided comprising the steps of:

providing a frame attachment portion adapted for connection to a vehicle frame rail having a first spring module attached to the frame attachment portion, wherein the first spring module has an opening defined by a top wall, a bottom wall, a first side wall, and a second side wall of the first spring module;

positioning a first part of a first spring mount within the opening;

positioning a first shear spring between a first tapered surface of the first spring mount and a first side wall of the opening of the first spring module;

positioning a second shear spring between a second tapered surface of the first spring mount and second side wall of the opening of the first spring module;

positioning a second part of the first spring mount within the opening;

placing a first threaded connecting rod through a through-hole in at least one of the first part of the first spring mount or the second part of the first spring mount; and

tightening the first threaded connecting rod to draw together the first part of the first spring mount and the second part of the first spring mount, and to compress the first shear spring between the first side wall of the first spring mount and the first side wall of the opening of the first spring module, and also to compress the second shear spring between the second side wall of the first spring mount and the second side wall of the opening of the first spring module.

In another aspect, a saddle assembly for use in a vehicle suspension is provided comprising an inboard saddle having a bottom mount section, said inboard saddle including an upper first end comprising an inboard part of a first spring mount and an upper second end comprising an inboard part of a second spring mount, wherein the upper first and second ends are positioned above the bottom mount of the inboard saddle, an outboard saddle having a bottom mount section, said outboard saddle including an upper first end comprising an outboard part of a first spring mount and an upper second end comprising an outboard part of a second spring mount, wherein the upper first and second ends are positioned above the bottom mount of the outboard saddle, wherein the upper first ends of the inboard saddle and the outboard saddle have been drawn together by a first threaded connecting rod that passes through at least one of the inboard and outboard parts of the first spring mount, and the upper second ends of the inboard saddle and the outboard saddle have been drawn together by a second threaded connecting rod that passes through at least one of the inboard and outboard parts of the second spring mount, and wherein the inboard and outboard parts of the first spring mount have been drawn together into contact and together form the first spring mount, and the inboard and outboard parts of the second spring mount have been drawn together into contact and together form the second spring mount.

In another aspect, a load cushion for a suspension system is provided comprising:

a base and cushion portion extending from the base in a first direction, and

a first load cushion retainer extending from the base in a second direction.

BRIEF DESCRIPTION OF THE DRAWINGS

Exemplary embodiments of the invention are described herein with reference to the drawings, wherein like parts are designated by like reference numerals, and wherein:

FIG. 1 is a perspective view of a vehicle suspension 50;

FIG. 2 is a perspective view of vehicle suspension 50 shown in FIG. 1;

FIG. 3 is an elevation view of the vehicle suspension 50 shown in FIGS. 1 and 2;

FIG. 4 is a perspective view of a frame hanger component of vehicle suspension 50 shown in FIGS. 1-3;

FIG. 5 is another perspective view of the frame hanger component of FIG. 4;

FIG. 6 is a perspective view of a saddle assembly shown in FIGS. 1-3;

FIG. 7 is another perspective view of the saddle assembly shown in FIG. 6;

FIG. 8 is a perspective view of a portion of the saddle assembly shown in FIGS. 6 and 7;

FIG. 8A is another perspective view of the portion of the saddle assembly shown in FIGS. 6 and 7;

FIG. 9 is a perspective view of a shear spring used in the vehicle suspension shown in FIGS. 1-3;

FIG. 10 is an elevation view of the shear spring in FIG. 9;

FIG. 11 is another elevation view of shear spring shown in FIGS. 9 and 10;

FIG. 12 is a plan view of the shear spring shown in FIG. 9;

FIG. 13 is another perspective view of shear spring shown in FIGS. 9-12;

FIG. 14 is a perspective view of a load cushion used in the vehicle suspension of FIGS. 1-3;

FIG. 15 is another perspective view of the load cushion of FIG. 14;

FIG. 16 is an elevation view of the load cushion of FIGS. 14 and 15;

FIG. 17 is a plan view of the load cushion shown in FIGS. 14-16;

FIG. 18 is another plan view of the load cushion shown in FIGS. 14-17;

FIG. 19 is a perspective view of a load cushion;

FIG. 20 is a perspective view of a load cushion;

FIG. 21 a is a top view of an inboard saddle and an outboard saddle prior to being drawn together by two connecting rods;

FIG. 21 b is a top view of the saddles in FIG. 21 a after they have been drawn together by the connecting rods;

FIG. 22 is a view of the outboard side of vehicle suspension 50;

FIG. 23 is a cross sectional top view of the vehicle suspension 50 of FIG. 22 along line 23-23 shown in FIG. 22;

FIG. 24 is a bottom view of the vehicle suspension 50 shown in FIGS. 2 and 3;

FIG. 25 a is an elevation view of the vehicle suspension 50 shown in FIGS. 2 and 3;

FIG. 25 b is another elevation view of the vehicle suspension 50 shown in FIGS. 2 and 3;

FIG. 26 is a view of an alternate embodiment showing vehicle suspension 450;

FIG. 27 is a view of vehicle suspension 650;

FIG. 28 is a view of an alternate vehicle suspension 550;

FIG. 29 is a view of a spring mount;

FIG. 30 is a perspective view of another example vehicle suspension;

FIG. 31 is a perspective view of another example vehicle suspension; and

FIG. 32 is a load cushion having two load cushion retainers extending from the base.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1 is a perspective view of a vehicle suspension 50 having a frame attachment portion 58 that is adapted for attachment to a vehicle frame or frame rail. Vehicle suspension 50 is shown attached to a walking beam 78 positioned beneath the vehicle suspension 50. Also disclosed is a second vehicle suspension 50 a having a frame attachment portion 58 a that is adapted for attachment to a vehicle frame or frame rail on a side of the vehicle opposite the side to which vehicle suspension 50 is attachable to a vehicle frame or frame rail. Vehicle suspension 50 a is shown attached to a walking beam 78 a positioned beneath the vehicle suspension 50 a. A cross tube 55 is attachable to vehicle suspensions 50 and 50 a.

Vehicle suspension 50 is designed to support longitudinally extending vehicle frame rails (not shown) which can be of various types that are positioned above laterally extending vehicle axles. As will be appreciated by those skilled in the art, components of vehicle suspension 50 and the other suspensions described herein are duplicated on each side of the vehicle as shown in FIG. 1. It will also be appreciated that vehicle wheels may be mounted to the ends of the vehicle axles in a known manner. Further, it will be appreciated that the vehicle frame rails may be connected by one or more vehicle frame cross members.

Those skilled in the art will further understand that a suspension, arranged in accordance with the suspension 50 and the components thereof, alternatively may be attached to frame rails of a trailer (for example, a trailer that connects to a semi-tractor). The frame rails of a trailer may comprise frame rails such as those described above or another type of frame rail.

For purposes of this description, unless specifically described otherwise, hereinafter, “vehicle” refers to a vehicle or a trailer. In this way, for example, a vehicle frame refers to a vehicle frame or a trailer frame. Furthermore, for purposes of this description, the left side of a vehicle refers to a side of the vehicle on an observer's left-hand side when the observer faces the back of the vehicle, and the right side of the vehicle refers to a side of the vehicle on an observer's right-hand side when the observer faces the back of the vehicle. Furthermore still, for purposes of this description, “outboard” refers to a position further away from a center line, running from the front to the back of a vehicle, relative to “inboard” which refers to a position closer to that same center line.

Top edges 57 and 57 a of frame attachments portions 58 and 58 a, respectively, have a center portion that does not extend as far as the end portions of top edges 57 and 57 a on both sides of the center portions. As an example, those center portions may be arranged in such configurations so as to allow frame attachment portions 58 and 58 a to be attached to frame rails that have features that would interfere with the attachment of frame attachment portions having center portions that extend to the same level as the end portions.

FIG. 1 identifies walking beam ends 59 and 59 a. In accordance with a first embodiment, frame attachment portion 58 may be attached to a frame rail on the left side of a vehicle and the frame attachment portion 58 a may be attached to a frame rail on the right side of the vehicle such that the front end of the vehicle is closer to walking beam end 59 than it is to walking beam end 59 a. In accordance with a second embodiment, frame attachment portion 58 may be attached to a frame rail on the right side of the vehicle and the frame attachment portion 58 a may be attached to a frame rail on the left side of the vehicle, such that the front end of the vehicle is closer to walking beam end 59 a than it is to walking beam end 59.

FIG. 2 is a perspective view of vehicle suspension 50 (the same suspension shown in FIG. 1). Frame rail attachment holes 60 of frame attachment portion 58 are adapted for attaching frame attachment portion 58 to a vehicle frame or frame rail (not shown) using, for example, connecting rods, such as mounting bolts. Vehicle suspension 50 includes gussets 62 a-f extending perpendicularly from the frame rail attachment portion 58 to provide additional support and rigidity to vehicle suspension 50.

A spring module 70 is attached to frame rail attachment portion 58. Spring module 70 includes an opening 64. Positioned within opening 64 are (i) at least a part of a spring mount 66, (ii) at least a part of a first shear spring 72 positioned between a first side wall of the spring mount 66 and a side wall 80 of spring module 70, (iii) at least a part of a second shear spring 74 positioned between a second side wall of the spring mount 66 and a second side wall of spring module 70, and (iv) at least a part of a load cushion 76 positioned on top of spring mount 66 and beneath the top wall 84 of spring module 70.

Similarly, but adjacent to spring module 70, a spring module 70 a is attached to frame rail attachment portion 58. Spring module 70 a includes an opening 64 a. Positioned within opening 64 a are (i) at least a part of a spring mount 66 a, (ii) at least a part of a shear spring 72 a positioned between a first side wall of the spring mount 66 a and a side wall 80 a (see FIG. 4) of spring module 70 a, (iii) at least a part of a shear spring 74 a positioned between a second side wall of the spring mount 66 a and a side wall 82 a of spring module 70, and (iv) at least a part of a load cushion 76 a positioned on top of spring mount 66 a and beneath the top wall 84 a (see FIG. 3) of spring module 70 a. As used herein, where it is stated that a component is positioned within the opening, that encompasses situations where the component is not entirely positioned within the opening. Thus, components partially, but not entirely, positioned within the opening are still positioned within the opening within the meaning of this specification.

FIG. 3 shows an elevation view of vehicle suspension 50 (i.e., the same suspension shown in FIGS. 1 and 2). Spring module 70 is shown attached to frame rail attachment portion 58. Spring module 70 includes an opening 64. Positioned within at least a portion of opening 64 are (i) a spring mount 66, (ii) a shear spring 72 positioned between a first side wall of spring mount 66 and a first side wall 80 of opening 64, (iii) a shear spring 74 positioned between a second side wall of spring mount 66 and a side wall of 82 of opening 64, and (iv) a load cushion 76 positioned on top of spring mount 66 and beneath a top wall 84 of opening 64.

A second spring module 70 a is positioned adjacent spring module 70 and is also attached to frame rail attachment portion 58. Spring module 70 a includes an opening 64 a. Positioned within at least a portion of opening 64 a are (i) a spring mount 66 a, (ii) a third shear spring 72 a positioned between a first side wall of spring mount 66 a and a side wall 80 a of opening 64 a, (iii) a fourth shear spring 74 a positioned between a second side wall of the spring mount 66 a and a second side wall 82 a of opening 64 a, and (iv) a load cushion 76 a positioned on top of spring mount 66 a and beneath a top wall 84 a of opening 64 a.

FIGS. 4 and 5 are perspective views of a frame hanger portion (or more simply, a “frame hanger”) 100 that is a component of vehicle suspension 50 shown in FIGS. 1-3. Frame hanger 100 comprises frame attachment portion 58, gussets 62 a-f, upper U-plates 73 and 77, and lower U-plates 75 and 79. Each of U-plates 73, 75, 77, and 79 can consist of a single plate formed from a single flat plate, or alternatively, can be fabricated from multiple flat plates. Alternately, the U-plates can be cast. Further, the entire opening 64 of spring module 70, or portions thereof, could be cast as well.

Upper U-plate 77 and lower U-plate 79 define opening 64 of spring module 70. Upper U-plate 77 includes flanges 77 a and 77 b and top wall 84. U-plate 79 includes side walls 80 and 82 and bottom wall 86. Preferably, a distance 101 (shown in FIG. 5) between the outer edges of flanges 77 a and 77 b is equal to or slightly less than a distance 102 (shown in FIG. 5) between walls 80 and 82 such that upper U-plate 77 fits between walls 80 and 82 and flanges 77 a and 77 b are operable as shear spring stops 84 b and 84 c for shear springs 72 and 74, respectively.

Similarly, upper U-plate 73 and lower U-plate 75 define opening 64 a of spring module 70 a. Upper U-plate 73 includes flanges 73 a and 73 b and top wall 84 a. U-plate 75 includes side walls 80 a and 82 a and bottom wall 86 a. Preferably, a distance 103 (shown in FIG. 5) between the outer edges of flanges 73 a and 73 b is equal to or slightly less than a distance 104 (shown in FIG. 5) between walls 80 a and 82 a such that upper U-plate 73 fits between walls 80 a and 82 a and flanges 73 a and 73 b are operable as shear spring stops 84 e and 84 d for shear springs 72 a and 74 a, respectively. Preferably, distance 101 equals distance 103, and distance 102 equals distance 104. FIG. 4 illustrates side edges 110, 110 a, 110 b, and 110 c of side walls 80, 82, 80 a, and 82 a, respectively, and FIG. 5 illustrates side edges 112, 112 a, 112 b, and 112 c of side walls 80, 82, 80 a, and 82 a, respectively.

It should be noted the top wall 84 of the U-plate 77 and/or the top wall 84 a of U-plate 73 may include a dome-like configuration to control bulging of a progressive spring rate load cushion during loaded conditions thereby increasing the useful life of the load cushion. The load cushion may be an elastomeric progressive spring rate load cushion shaped to resemble a pyramid, and having a flattened top surface (see FIG. 14 described below). The top of the load cushion nests within the dome-like configuration during loading. The dome-like configuration may be formed in top wall 84 or 84 a by a stamping or punching operation where the top wall of the plate is plastically deformed. Alternately, a dome could be cast or forged into the top wall of the opening. In addition, a domed insert (e.g., a cast or forged dome insert) could be attached (e.g., by welding or bolting) to the top wall to provide a top wall with a dome-like configuration.

Lower U-plate 79 includes a weld-slot 81 through which a weld bead (not shown) for welding lower U-plate 79 to lower U-plate 75 can reside without extending outside of weld-slot 81. In accordance with an example embodiment, the weld bead within weld-slot 81 may be the only weld bead within opening 64, such that opening 64 includes no weld beads that can act as ramps upon which shear springs 72 or 74 can ride on to avoid shear spring stops 84 b or 84 c, respectively.

Similarly, U-plate 75 includes a weld-slot (not shown) through which a weld bead (not shown) for welding lower U-plate 75 to lower U-plate 79 can reside without extending outside of the weld-slot within U-plate 75. In accordance with an example embodiment, the weld bead within the weld-slot within U-plate 75 may be the only weld bead within opening 64 a, such that opening 64 a includes no weld beads that can act as ramps upon which shear springs 72 a or 74 a can ride on to avoid shear spring stops 84 d or 84 e, respectively. Preferably, the weld-slot within U-plate 75 has the same shape and orientation as weld-slot 81 and is located closer to edge 110 a of wall 86 a than to edge 112 b of wall 86 a.

FIG. 4 further illustrates a pocket 37 positioned on side wall 82 a. Pocket 37 is shown in dashed lines because pocket 37 is not required for use with shears springs configured as shear springs 72, 72 a, 74, 74 a, and 300. Rather pocket 37 might be used with shear springs having a flat base plate without outwardly extending flanges (described below). In accordance with embodiments in which pockets are used to retain shear springs, such pockets are typically located on the opposing side walls of the spring module. Details regarding pockets are shown and described in U.S. Pat. No. 7,926,836.

It should be noted that while the above embodiments are shown constructed using U-shaped plates, U-shaped plates are not required. In fact, the top wall, bottom wall, and first and second side walls that define the opening could each be separate plates, or otherwise constructed without using U-shaped plates, although using U-shaped plates to define the opening is preferred in the above embodiments.

FIGS. 6 and 7 are perspective views of a saddle assembly 90 that is shown in FIGS. 1-3 and that comprises an outboard saddle 120 and an inboard saddle 130. FIGS. 8 and 8A are perspective views of outboard saddle 120. In accordance with the embodiments described herein, inboard saddle 130 may be identical to outboard saddle 120. Alternatively, inboard saddle 130 may be identical to outboard saddle 130 except that the mounting holes (e.g., mounting holes 205, 205 a) into which connecting rods 146 and 146 a are installed in one of those saddles may be tapped holes and the mounting holes in the other saddle may be untapped holes.

Saddles 120, 130 each include upper and bottom portions. Each upper portion of saddles 120, 130 includes two spring mount portions. Each of the two spring mount portions of saddle 120 interface to corresponding spring mount portions of saddle 130 to form respective spring mounts 66 and 66 a. The bottom portion of outboard saddle 120 includes a bottom mount section 136, and the bottom portion of inboard saddle 130 includes a bottom mount section 134. Those bottom mount sections may be conical, spherical, or wedge shaped, and may form a mechanical joint when attached to a walking beam as is known in the art. Furthermore, the bottom portions of outboard saddle 120 and inboard saddle 130 may be similar to the bottom portions of saddles disclosed in U.S. Pat. No. 7,926,836.

As shown in one or more FIGS. 6, 7, 8, and 8A, the upper portion of outboard saddle 120 is identified as upper portion 140, and the upper portion of inboard saddle 130 is identified as upper portion 142. As shown in FIG. 8 and/or FIG. 8A, upper portion 142 includes a spring mount portion 143 and a spring mount portion 145. Spring mount portion 143 includes spring mount side portions 143 a and 143 b and spring mount portion interface 143 f. Similarly, spring mount portion 145 includes spring mount side portions 145 a and 145 b and spring mount portion interface 145 f. Each spring mount side portion of upper portions 140 and 142 includes a pair of flanges and a tapered surface.

As shown in FIG. 8, spring mount side portion 143 a includes flanges 143 c and 143 d and tapered surface 191 a, and spring mount side portion 145 b includes flanges 145 c and 145 d and tapered surface 191 b. As shown in FIG. 8A, spring mount side portion 143 b includes flanges 143 e and 143 g and tapered surface 191 c, and spring mount side portion 145 a includes flanges 145 e and 145 g and tapered surface 191. Each flange on the spring mount side portions include a surface that is operable as a positive-stop to restrict a shear spring from moving beyond the positive-stop as the shear spring is moving in a direction towards the positive-stops. Examples of the shear spring positive-stops on the spring mount side portions shown in FIGS. 6 and 7 includes flange surfaces 173 a, 173 b, 173 c, 173 d, 173 e, 173 f, 173 g, 173 h, 173 i, and 173 j.

Upper portions 140, 142 of saddles 120, 130 include a number of significant advantages over the saddles and saddle assemblies shown in U.S. Pat. No. 7,926,836. As one example, the upper portions 140, 142 of saddles 120, 130 are designed to be drawn together (e.g., drawn in contact with each other) by connecting rods 146 and 146 a. In that way, spring mount portion interface 143 f is drawn into contact with a corresponding spring mount portion interface on upper portion 140 and spring mount portion interface 145 f is drawn into contact with another corresponding spring mount portion interface on upper portion 140.

In accordance with this design, the upper portions 140, 142 may serve as spring mounts. In particular, the upper portions 140, 142 include first ends 150, 152 thereof that together form first load cushion mounting surface 155 on first spring mount 66 that is adapted to have a first load cushion mounted thereon. Similarly, upper portions 140, 142 also include second ends 160, 162 thereof that together form second load cushion mounting surface 165 on second spring mount 66 a that is adapted to have a second load cushion mounted thereon. Of course, while two load cushion mounting surfaces are shown, only one, or perhaps three or more load cushion mounting surfaces could be provided on the upper portions 140, 142. Thus, spring mounts 66 and 66 a are integrally attached to the saddle, unlike the saddle shown in U.S. Pat. No. 7,926,836. Indeed, spring mounts 66 and 66 a are preferably integrally formed with the saddles 120 and 130, as shown in FIG. 6. With this design, the need for separate spring mounts is eliminated. Of course, spring mounts integral with the saddle are not required and spring mounts that are separate from the saddle may be used for particular applications, as shown for example in FIG. 27.

As mentioned above, the upper portions 140, 142 of the outboard saddle 120 and inboard 130 are connected together. As discussed in greater detail below, a threaded connecting rod may be a bolt, screw, or other suitable fastener and may be used to connect the saddles together. As illustrated in FIG. 6, one end of connecting rods 146 and 146 a can be seen indicating where the connection of the saddles may be accomplished.

FIG. 7 further illustrates the threaded shank portions of connecting rods 146 and 146 a. The threaded portion of the connecting rod 146 can be seen extending through the saddles 120, 130 and with nut 204 attached to the threaded portion so as to connect the saddles together. Similarly, the threaded portion of the connecting rod 146 a can be seen extending through the saddles 120, 130 and with nut 204 a attached to the threaded portion so as to connect the saddles together.

Depending on the application, the disclosed vehicle suspensions may not utilize load cushions on the top surface of the spring mounts, and thus the load cushion mounting surfaces 155 and 165 may not be necessary. However, even in the absence of load cushion mounting surfaces, with the design of the saddle assembly shown in FIGS. 6 and 7, the upper portions 140, 142 may still serve as a spring mount. In particular, the upper portions 140, 142 include first ends 150, 152 thereof that together form a first V-shaped side wall 190 of spring mount 66, that is adapted to contact and compress a first shear spring having a corresponding V-shaped surface (not shown, but see below).

Similarly, upper portions 140, 142 also include second ends 160, 162 thereof that together form a second V-shaped side wall 190 a of the spring mount 66 a, that is adapted to contact and compress a second shear spring having a corresponding V-shaped top surface (also not shown, but see below). While V-shaped side walls 190 and 190 a are disclosed, the saddles could be designed such that only ends 150 and 152 or ends 160 and 162 include a V-shaped side wall. Again, with the design shown in FIG. 6, the need for a separate spring mount to contact a shear spring is eliminated.

As described above, there are two openings (64 and 64 a) in vehicle suspension 50. The saddle assembly 90 also includes a third V-shaped wall 190 b positioned between side walls 190 and 190 a, as well as a fourth V-shaped wall 190 c opposite from V-shaped wall 190 b and between side walls 190 and 190 a. V-shaped walls 190 b and 190 c, along with side walls 82 and 80A, respectively, are also adapted to contact and compress additional shear springs having corresponding V-shaped surfaces (not shown, but see below).

Furthermore, upper portion 142 of inboard saddle 130 includes positive-stops 171 a, 171 c, 171 e, and 171 g. Similarly, upper portion 140 of outboard saddle 120 includes positive-stops 171 b, 171 d, 171 f, and 171 h. Each of the foregoing positive-stops extends upward above load cushion mounting surfaces 155, 165, and is operable to prevent vehicle suspension 50 from having a longer than desired stroke. Those positive-stops are most-likely put into use when load cushions are not mounted to saddle assembly 90 or if the load cushion(s) mounted to saddle assembly 90 are compressed to a level below the upper surfaces of the positive-stops. During such use, the positive-stops can contact top walls 84 and 84 a so as to limit the stroke of vehicle suspension 50. Furthermore still, as shown in FIG. 8 and/or FIG. 8A, upper portion 142 of inboard saddle 130 includes positive-stops 171 w, 171 x, 171 y, and 171 z. Each of the foregoing positive-stops, as well as similarly positioned positive-stops on upper portion 140 of outboard saddle 120, is operable to prevent vehicle suspension 50 from having a longer than desired stroke. The positive-stops 171 w, 171 x, 171 y, and 171 z are most-likely put into use during a rebound motion of vehicle suspension 50. During such use, the positive-stops can contact bottom walls 86 and 86 a so as to limit the stroke of vehicle suspension 50. FIG. 8 and/or FIG. 8A further illustrates surface 155 a which provides one half of load cushion mounting surface 155 shown in FIGS. 6 and 7, and surface 165 a which provides one half of load cushion mounting surface 165 shown in FIGS. 6 and 7. Thus, surface 155 a is part of an inboard part 66 b of first spring mount 66 shown in FIGS. 6 and 7, and surface 165 a is part of inboard part 66 c of second spring mount 66 a shown in FIGS. 6 and 7.

FIG. 8 also illustrates tapered surface 191 a that forms one half of V-shaped wall 190 a at end 162 of saddle assembly 90, and tapered surface 191 b that forms one half of V-shaped wall 190 b shown in FIGS. 6 and 7. Further, through-hole 205 is shown in inboard part 66 b of first spring mount 66 which comprises half of spring mount 66, and through-hole 205 a is shown in inboard part 66 c of second spring mount 66 a which comprises half of second spring mount 66 a. As can be seen from FIGS. 7 and 8, connecting rod 146 extends through through-hole 205 and connecting rod 146 a extends through through-hole 205 a.

FIG. 8A also illustrates tapered surface 191 that forms one half of V-shaped wall 190 at end 152 of saddle assembly 90, and tapered surface 191 c that forms one half of V-shaped wall 190 c shown in FIGS. 6 and 7.

The frame hanger 100 of vehicle suspension 50 shown in FIGS. 4 and 5 may comprise cast or fabricated metal or composite material, including iron, steel, or aluminum. As shown in FIG. 4, frame hanger 100 is fabricated with gussets 62 a-f, and sheet steel may be used to make frame attachment portion 58. Frame hanger 100 could also be cast with any suitable castable material. Similarly, the saddles may comprise cast or fabricated metal or composite material. Depending on the application, the metal may, for example, be nodular ductile iron (or more simply, ductile iron), steel, such as a high strength low alloy steel, or aluminum. Typically, high strength low alloy steels are a preferred material to use for the frame hanger and the saddle, although aluminum is often desired when weight considerations are of greater importance.

FIGS. 9 and 13 are perspective views of a shear spring 300, which is sometimes referred to as a V-spring. Any of the shear springs disclosed in the example embodiments, such as shear springs 72, 72 a, 74, and 74 a, may be arranged as shear spring 300. As shown in FIG. 9, shear spring 300 includes a base plate 302, a V-shaped plate 310, and an intermediate plate 312. V-shaped plate 310 results in shear spring 300 having a V-shaped wall 310 a that is adapted to contact a corresponding V-shaped side wall of a spring mount. Shear spring 300 includes an elastomeric section 306 between base plate 302 and intermediate plate 312, and an elastomeric section 308 between intermediate plate 312 and V-shaped plate 310. Alternatively, the shear spring could be made without one or more of plates 302, 310, and 312. For example, the shear spring could be all elastomer, have a base plate 302 without plates 310 and 312, have base plate 302 and plate 312 but no intermediate plate 312, etc. Furthermore, base plate 302 could also be V-shaped like plates 310 and 312 such that all three plates are V-shaped. In such a case, the side wall of the opening contacting base plate 302 could also have a corresponding V-shape. Moreover, the shear spring 300 is shown having the geometry of a preferred embodiment. It will be appreciated that the base plate 302 may not even include a plate as noted above. Further, the base or base plate 302 of the shear spring 300 could also be affixed to the side walls of the opening in the spring module using fasteners, bolts, etc. in a known and conventional manner. Thus, the shear spring is not required to have, but may have, the geometry shown in FIGS. 9-13.

FIGS. 10 and 11 are elevational views of shear spring 300. Shear spring 300 has a free-state vertical offset 301 between its end plates (i.e., base plate 302 and V-shaped plate 310). Preferably, the free-state vertical offset 301 is equal to half the vertical travel of vehicle suspension 50. This is done to minimize a couple induced in shear spring 300 by virtue of the compression load acting on shear spring 300 applied at both end plates. A couple is a moment induced when equal and opposing forces are acting on a body but are not collinear. The effect of the couple on shear spring 300 is to induce rotation within the spring that could cause the spring to rotate within a spring module sufficiently enough to relieve the shear spring's compression and put the elastomeric sections (e.g., elastomeric sections 306 and 308) into tension. Offsetting both endplates of shear spring 300 by a distance equal to half of the suspension's vertical travel results in couples at the fully stroked and rebound conditions being equal but opposite in direction (the magnitude of these couples is half that of a spring with no offset or an offset equal to that of the vertical travel of vehicle suspension 50).

A shear spring is typically constructed from relatively flat first and second end plates with an elastomer connected between them. This spring will then have compressive and shear rates corresponding to the chosen material, cross-section, and thickness of elastomer. If one were to insert a third plate between the first and second end plates; such that, it subdivides the elastomer thickness into two separate, but not necessarily equal, thickness; the spring's compressive rate would increase while the shear rate would not be effected. Because the spring's plates are all relatively flat, the spring's shear rates in mutually perpendicular directions are the same.

If the spring has one or more plates with form; such that, the form confines the elastomer at least partially in one of the shear directions (use of V-plates is one way); the spring is no longer acting in pure shear in the confining direction. Rather, the spring is acting in a combination of shear and compression in the confining direction. The result is the confined shear direction having a higher effective shear rate than the unconfined shear direction. Just like above where the addition of plates to subdivide the rubber increases the compressive rate of the spring, the addition of formed plates will increase the compressive rate portion of the effective shear rate resulting in even higher effective shear rates.

FIG. 12 is a plan view of shear spring 300 comprising base plate 302, V-shaped plate 310, and intermediate plate 312. Base plate 302 includes a first flange 304 extending from a first end thereof away from V-shaped plate 310 and a second flange 305 extending from a second end thereof also away from V-shaped plate 310. Base plate 302 is adapted to contact a first side wall of a spring module opening of a vehicle suspension (for example, side wall 80 of opening 64 in the spring module of vehicle suspension 50). Frictional forces acting on shear spring 300, a side wall of a spring module opening, and a V-shaped side wall of a spring mount provide a primary means to prevent lateral movement of shear spring 300. The first flange 304 and the second flange 305 of base plate 302 are designed to extend beyond first and second side edges of a side wall of a spring module opening to secondarily restrict lateral movement of shear spring 300 with respect to vehicle suspension 50.

Intermediate plate 312 provides additional resistance to lateral shear forces acting on shear spring 300, such as lateral shear forces in a direction from flange 304 to flange 305 or from flange 305 to flange 304. Intermediate plate 312 is shown as having a V-shaped configuration with the same angle as V-shaped plate 310. However, intermediate plate 312 could have a larger or smaller angle for the V-shape as desired. Further, intermediate plate 312 could be omitted or additional intermediate plates (e.g., intermediate V-shaped plates) could be included between V-shaped plate 310 and base plate 302. Alternatively, an intermediate plate (e.g., intermediate plate 312) could be a flat plate, like the flat portion of base plate 302 between flanges 304 and 306, and additional plates could be added depending on the application or desired performance.

The V-shaped plates 310 and 312 may be bent from straight plates. Since V-shaped plate 310 has a V-shape, V-shaped plate 310 has an angle that is less than 180 degrees. FIG. 12 illustrates an included angle 311 formed by V-shaped plate 310 and an included angle 313 formed by intermediate plate 312. In the embodiments in which intermediate plate 312 has a V-shape, the included angles 311 and 313 are preferably the same number of degrees. The number of degrees (°) of included angles 311 and 313 may be a number of degrees that fall within any of a plurality of angle ranges including, but not limited to, the angle ranges of (i) 90° to 179°, (ii) 90° to 170°, or (iii) 115° to 125°. In accordance with that latter range, the included angles 311 and 313 may, for example, be 115°, 116°, 117°, 118°, 119°, 120°, 121°, 122°, 123°, 124°, 125° or some non-whole number angle between any two of those listed angles.

In accordance with the disclosed embodiments, shear spring 300 may be constructed of elastomeric sections 306 and 308 bonded to plates 302, 310, and 312. Elastomeric sections 306 and 308 may comprise an elastomeric material (i.e., an elastomer) such as natural rubber, synthetic rubber, styrene butadiene, synthetic polyisoprene, butyl rubber, nitrile rubber, ethylene propylene rubber, polyacrylic rubber, high-density polyethylene, thermoplastic elastomer, a thermoplastic olefin (TPO), urethane, polyurethane, a thermoplastic polyurethane (TPU), or some other type of elastomer. In this regard and in particular, elastomeric sections 306 and 308 may comprise an elastomer defined as American Society of Testing and Materials (ASTM) D2000 M4AA 717 A13 B13 C12 F17 K11 Z1 Z2. In this case, Z1 represents natural rubber and Z2 represents a durometer selected to achieve a desired shear rate. The selected durometer may be based on a given predefined scale, such as the Shore A scale, the ASTM D2240 type A scale, or the ASTM D2240 type D scale. In a preferred embodiment, in accordance with the Shore A scale, Z2, for example, is preferably 70±5. In another embodiment, in accordance with the Shore A scale, Z2 is, for example, within the range of 50 to 80. Other examples of Z2 and ranges for Z2 are also possible.

In another respect, elastomeric sections 306 and 308 may comprise a viscoelastomeric material that (i) has elastic characteristics when the shear spring 300 is under a load within a given range and when that load is removed, and (ii) has non-elastic characteristics (for example, does not return to an original non-loaded shape) if the applied load exceeds the greatest load of the given range. The given range may extend from no load to a maximum expected load plus a given threshold. The given threshold accounts for possible overloading of shear spring 300. As an example, the viscoelastomeric material may comprise amorphous polymers, semi-crystalline polymers, and biopolymers. Other examples of the viscoelastomeric material are also possible.

In accordance with the example embodiments, elastomeric sections 306 and 308 may also comprise one or more fillers. The filler(s) may optimize performance of elastomeric sections 306 and 308. The fillers may include, but are not limited to, wax, oil, curing agents, and/or carbon black. Such fillers may optimize performance by improving durability and/or tuning elastomeric sections 306 and 308 for a given shear load and/or a given compressive load applied to elastomeric sections 306 and 308. Improving durability through the use of fillers may include, for example, minimizing a temperature rise versus loading characteristic of elastomeric sections 306 and 308 and/or maximizing shape retention of elastomeric sections 306 and 308.

Shear spring 300 may be formed, for example, by inserting the plates 302, 310, and 312 into a mold (not shown). The plates may each be coated with a coating material. As an example, the coating material may comprise a material comprising zinc and phosphate, modified with calcium. The coating material may have a coating weight of 200-400 milligrams per square foot. Other examples of the coating material are also possible. A bonding agent may be applied to the coated plates for bonding the plates 302, 310, and 312 to elastomeric sections 306, 308. As an example, the bonding agent may comprise Chemlok® manufactured by the Lord Corporation, Cary, N.C., USA. Other examples of the bonding agent are also possible. Applying the coating material and/or applying the bonding agent may occur prior to, during, and/or after insertion of the plates 302, 310, 312 into the mold. After applying the coating material and the bonding agent, the elastomeric material (while in a pourable form) may be inserted into the mold to form the elastomeric sections 306, 308.

In a preferred embodiment, any exposed portion of the plates 302, 310, and 312 (for example, a portion of the plates not covered by the elastomeric material) is protected against corrosion by a means other than the elastomeric material. In other embodiments, some exposed portions of the plates 302, 310, and 312 (e.g., the edges of the plates) may not be protected against corrosion, whereas any other exposed portions of the plates are protected against corrosion.

The plates 302, 310, and 312 can be made of any of a variety of suitable materials, including, but not limited to, iron, steel, aluminum, plastic, a composite material, or some other material. The plates 302, 310, 312 may be fully, or at least substantially, encapsulated in elastomer to further enhance their corrosion resistance and friction at the mating suspension members. As an example, plates 302, 310, and 312 can comprise plates having a thickness between a range of 0.125 inches (3.175 mm) to 0.25 inches (6.35 mm).

In accordance with an example embodiment, the desired vertical shear rate of the shear spring 300 is approximately 615 N/mm (or approximately 3,500 pound force per inch (i.e., lb_(f)/in)), and the initial compressive spring rate of the shear spring 300 is approximately 5,700 N/mm (or approximately 32,500 lb_(f)/in).

FIGS. 14 and 15 are perspective views of an example load cushion 400 for use in vehicle suspension 50. FIG. 16 is an elevation view of load cushion 400 and FIGS. 17 and 18 are top and bottom plan views, respectively, of load cushion 400. Any of the load cushions disclosed in the example embodiments, such as load cushions 76 and 76 a, may be arranged as load cushion 400.

As shown in one or more of FIGS. 14, 15, and 16, load cushion 400 includes a base 402, a load cushion portion 404, a mounting extension 406 with a mounting hole 407, and a mounting extension 408. A load cushion retainer 410, integral with load cushion 400, extends from mounting extension 408. Load cushion portion 404 is positioned between mounting extensions 406 and 408 and, as shown in FIG. 14, above base 402. The load cushion base 402 may comprise a metal plate that is either solid or includes gaps or voids, or may comprise elastomeric material or a combination thereof.

Load cushion portion 404 may be designed to have at least one tapered wall, and generally, similarly shaped horizontal cross sections of different sizes throughout. The size change factor, or ratio of similitude, is a function of the taper of at least one tapered wall. The horizontal cross sections can be any geometric shape desired for packaging, weight or aesthetics. Additionally, or alternatively, the horizontal cross sections can be selected to obtain a desired vertical spring rate for load cushion 400.

Load cushion retainer 410 includes a load cushion retainer grip (or more simply, a grip) 414, a load cushion retainer shaft (or more simply, a shaft) 415, and a load cushion retainer disc (or more simply, a disc) 416. The shaft 415 extends between an outer surface 402 a (see, FIG. 15) of base 402 and a retention surface 411 of disc 416. Grip 414 extends away from disc 416 from a portion of disc 416 opposite retention surface 411. The diameters of grip 414, shaft 415, and disc 416 may be different. For example, and as shown in FIG. 15, a diameter of shaft 415 is smaller than a diameter of disc 416, and a diameter of grip 414 is generally smaller (although not necessarily smaller) than the diameters of shaft 415 and disc 416.

A length of shaft 415 may be selected with respect to a height of a saddle assembly recess, such as one of recesses 420 and 421 of saddle 120 or one of recesses 422 and 423 of saddle 130. Typically, the length of shaft 415 is 10-15% less than the recess height. This allows the retainer to “clamp” itself into place. Furthermore, the diameter of shaft 415 may be selected with respect to a width of the saddle assembly recess. As an example, the length of shaft 415 may be selected to be slightly greater than the height of a saddle assembly recess and the diameter of shaft 415 may be selected to be slightly less than the depth and/or the width of the saddle assembly recess so that the shaft 415 can be positioned within the saddle assembly recess by hand.

Grip 414 may be used to pull or push shaft 415 into a saddle assembly recess, as well as to pull or push shaft 415 out of the saddle assembly recess. Load cushion retainer 410 may flex while grip 414 is pulled or pushed. A diameter of shaft 415, and thus the width of the saddle assembly recess, may be selected to be large enough such that load cushion retainer 410 is not torn from outer surface 402 a while a force to pull or push grip 414 is applied to load cushion retainer 410.

Mounting load cushion 400 to load cushion mounting surface 155 or 165 of the inboard and outboard saddles 120, 130 may include positioning shaft 415 into a recess on a load cushion mounting surface, such as either of recesses 420 and 423 on load cushion mounting surface 165 (shown in FIGS. 6 and 7), or either of recesses 421 and 422 on load cushion mounting surface 155 (shown in FIGS. 6 and 7). After shaft 415 is positioned within a saddle assembly recess of either the inboard or outboard saddle, a fastener, such as a bolt, a screw, a cotter pin, a hitch pin, a pine-tree style pin, a clevis pin, or some other type of fastener or combination of fasteners, can be inserted into mounting hole 407 and into the other saddle. In one respect, the other saddle may include a saddle assembly recess as shown in FIGS. 5 and 6. In another respect, the other saddle may include a tapped or non-tapped hole to which the fastener can be installed for retaining load cushion 404 at mounting extension 406. That tapped or non-tapped hole may be a through-hole. Furthermore, the load cushion retainer could also be positioned elsewhere on the load cushion.

FIG. 19 is a perspective view illustrating an alternative load cushion 400 a. Any of the load cushions disclosed in the example embodiments, such as load cushions 76 and 76 a, may be arranged as load cushion 400 a. Load cushion 400 a includes a base 402 a, a load cushion portion 404 a, a mounting extension 406 a, and a mounting extension 408 a. Base 402 a, load cushion portion 404 a, and mounting extension 408 a are the same as base 402, load cushion portion 404, and mounting extension 408, respectively, of load cushion 400. Load cushion portion 404 a is positioned between mounting extensions 406 a and 408 a and, as shown in FIG. 19, above base 402 a.

A load cushion retainer 417, integral with load cushion 400 a, extends from mounting extension 406 a. Load cushion retainer 417 includes a load cushion retainer grip (or more simply, a grip) 418, a load cushion retainer shaft (or more simply, a shaft) 413, and a load cushion retainer disc (or more simply, a disc) 412. Shaft 413 extends between an outer surface 403 a of base 402 a and a retention surface 419 of disc 412. Grip 418 extends away from disc 412 from a portion of disc 412 opposite retention surface 419. The foregoing components of load cushion retainer 417 may be configured similar to like named components of load cushion retainer 410 shown in FIG. 14.

Mounting load cushion 400 a to load cushion mounting surface 155 or 165 of inboard and outboard saddles 120, 130 may include positioning shaft 415 a into a recess on a load cushion mounting surface, such as either of recesses 421 and 423 on load cushion mounting surface 165 (shown in FIGS. 6 and 7), or either of recesses 420 and 422 on load cushion mounting surface 155 (shown in FIGS. 6 and 7). After shaft 415 a is positioned or while shaft 415 a is being positioned within a saddle assembly recess of either the inboard or outboard saddle, shaft 413 is positioned within another saddle assembly recess on the same load cushion mounting surface that includes the saddle assembly recess in which shaft 415 a was or is being positioned. Grips 414 a and 418 may be pushed or pulled for enabling easier installation of shafts 413 and 415 a into respective recesses.

FIG. 20 is a perspective view illustrating an alternative load cushion 400 b. Any of the load cushions disclosed in the example embodiments, such as load cushions 76 and 76 a, may be arranged as load cushion 400 b. Load cushion 400 b includes a base 402 b, a load cushion portion 404 b, a mounting extension 406 b, and a mounting extension 408 b. Base 402 b, load cushion portion 404 b, and mounting extension 406 b are the same as base 402, load cushion portion 404, and mounting extension 406, respectively, of load cushion 400. Load cushion portion 404 b is positioned between mounting extensions 406 b and 408 b and, as shown in FIG. 20, above base 402 b.

Mounting extension 406 b includes a mounting hole 407 b. Similarly, mounting extension 408 b includes a mounting hole 409. Mounting load cushion 400 b to load cushion mounting surface 155 or 165 of inboard and outboard saddles 120, 130 may include aligning mounting holes 407 b and 409 with a respective saddle assembly recess of either of load cushion mounting surface 155 or 165. A fastener separate from load cushion 400 b, such as a bolt, a screw, a cotter pin, or some other type of fastener, can be inserted into mounting hole 407 and into a saddle assembly recess, such as one of saddle assembly recesses 420, 421, 422, or 423 shown in FIGS. 6 and 7. Alternatively, a saddle to which load cushion 404 b is to be mounted may include a tapped or non-tapped hole to which the separate fastener can be installed for retaining load cushion 404 at mounting extension 406 b. That tapped or non-tapped hole may be a through-hole. The opposite saddle may include a similarly configured tapped or non-tapped hole to which another separate fastener can be installed for retaining load cushion 404 at mounting extension 408 b.

Alternately, as shown in FIG. 32, load cushion 400 c having base 402 c may include a first load cushion retainer 430 comprising a first load cushion 430 extending from base 402 c as well as a second load cushion retainer 440 also extending from base 402 c.

Load cushions 400, 400 a, 400 b, and 400 c preferably have a continuously increasing spring rate as an applied load increases and a continuously decreasing spring rate as an applied load decreases. Thus, the example vehicle suspensions, described herein, that use any of load cushions 400, 400 a, 400 b, and 400 c can advantageously have a continuously increasing spring rate as an applied load increases and a continuously decreasing spring rate as an applied load decreases. Load cushions 400, 400 a, 400 b, and 400 c act in compression and do not undergo tensile loading, so load cushions 400, 400 a, 400 b, and 400 c also have increased fatigue life over other springs (for example, elastomer springs) that are subjected to such loading.

In accordance with example embodiments, each load cushion 400, 400 a, 400 b, and 400 c is an elastomeric progressive spring rate load cushion shaped to resemble a pyramid. In one respect, the base and load cushion portion of load cushions 400, 400 a, 400 b, and 400 c are made of elastomer and do not include any plates or any bonding agents for bonding plates to elastomer. In another respect, the base of load cushions 400, 400 a, 400 b, and 400 c may include a plate (which can be referred to as a base plate) made of any of a variety of suitable materials, including, but not limited to, iron, steel, aluminum, plastic, and a composite material. As an example, the base plate can comprise a plate having a thickness between a range of 0.125 inches (3.175 mm) to 0.25 inches (6.35 mm). The base plate can be encapsulated in elastomer and/or bonded to the load cushion portion using a bonding agent. The base plate dimensions and shape can be varied to any dimension or shape desired for packaging, weight, and aesthetics. Preferably, each load cushion base is dimensioned to (i) match the top surface of a spring mount described herein, such as spring mount 66 or 66 a, (ii) locate mounting holes and/or load cushion retainer for securing the load cushion base to the spring mount, and (iii) minimize overall mass.

The size and dimensions of the elastomer used for the progressive spring rate load cushions 400, 400 a, 400 b, and 400 c may be optimized for the vertical spring rate requirements. For the present application, the vertical spring rate for the progressive spring rate load cushions 400, 400 a, 400 b, and 400 c continuously increases with increasing load and continuously decreases with decreasing load, defining a curvilinear shape with no discontinuities on a graph illustrating spring rate as a function of sprung load.

Preferably, load cushion portion 404 has a shape closely resembling a pyramid with a flattened top surface, as shown. With this preferred shape, the vertical spring rate for the load cushion 400 linearly increases with increasing load and linearly decreases with decreasing load. In that regard, load cushion 400 is operable as a progressive spring rate load cushion. In one embodiment, the cross section of load cushion portion 404 adjacent base 402 is 120 millimeters (mm) by 150 mm, the cross section of the top surface of load cushion portion 404 is 45 mm by 56 mm, the height of the load cushion portion 404 is 71 mm, and the height of base 402 is 9 mm. Other example dimensions of portions of load cushion 400 are also possible. For a given geometry, the spring rate of load cushion 400 may be optimized by varying the durometer of the elastomer. By varying the durometer, a family of interchangeable progressive spring rate load cushions can be created.

FIGS. 21 a and 21 b are top views of inboard saddle 130 and outboard saddle 120. FIG. 21 a shows inboard saddle 130 and outboard saddle 120 before a first connecting rod 146 and a second connecting rod 146 a are used to draw inboard saddle 130 and outboard saddle 120 together. FIG. 21 a shows connecting rod 146 extending through the inboard saddle and the outboard saddle with end 212 and nut 214 that will be tightened against the inboard saddle and outboard saddle to draw them together into contact. Similarly FIG. 21 a shows connecting rod 146 a extending through inboard saddle 130 and outboard saddle 120 with end 212 a and nut 214 a that will be tightened against the inboard saddle and the outboard saddle to draw them together into contact. Preferably, the ends 212 and 212 a of connecting rods 146 and 146 a are located within the outboard saddle such that the opposing ends of those connecting rods will not be in positions in which the opposing ends can make contact with tires or wheels that attach to axles connected to vehicle suspension 50.

FIGS. 21 a and 21 b illustrate shear spring 72 adjacent to first ends 150 and 152, and shear spring 74 a adjacent to second ends 160 and 162. Shear spring 72 has V-shaped wall 310 a adapted to contact the V-shaped side wall 190 of spring mount 66 (see FIGS. 6 and 7), wherein the shear spring 72 is positioned between side wall 80 of the opening of the first spring module and the V-shaped side wall 190. Prior to shear spring 72 being placed under a compression load by side wall 80 and V-shaped wall 190, the distance between V-shaped plate 310 of shear spring 72 and intermediate plate 312 of shear spring 72 is denoted by the letter “A,” and the distance between intermediate plate 312 of shear spring 72 and base plate 302 of shear spring 72 is denoted by the letter “B.”

Similarly, FIGS. 21 a and 21 b illustrate shear spring 74 a adjacent to second ends 160 and 162. Shear spring 74 a has a V-shaped wall 310 a adapted to contact the V-shaped side wall 190 a of spring mount 66 a (see FIGS. 6 and 7), wherein the shear spring 74 a is positioned between side wall 82 a of the opening of the second spring module and the V-shaped side wall 190 a. Prior to shear spring 74 a being placed under a compression load by side wall 82 a and V-shaped wall 190 a, the distance between V-shaped plate 310 of shear spring 74 a and intermediate plate 312 of shear spring 74 a is denoted by the letter “C,” and the distance between intermediate plate 312 of shear spring 74 a and base plate 302 of shear spring 74 a is denoted by the letter “D.”

FIG. 21 b shows inboard saddle 130 and outboard saddle 120 after nuts 214 and 214 a have been tightened onto connecting rods 146 and 146 a to draw inboard saddle 130 and outboard saddle 120 into contact with each other. While tightening nuts 214 and 214 a onto connecting rods 210 and 210 a together they also serve to cause (i) shear spring 72 to be compressed between V-shaped side wall 190 and side wall 80 of the opening of the first spring module 70, and (ii) shear spring 74 a to be compressed between V-shaped side wall 190 a and side wall 82 a of the opening of the second spring module 70 a. The tapered surfaces of the V-shaped side wall 190 contact and compress shear spring 72 by a wedging action in which the elastomeric sections 306 and 308 of shear spring 72 are compressed. Similarly, the tapered surfaces of the V-shaped side wall 190 a contact and compress shear spring 74 a by a wedging action in which the elastomeric sections 306 and 308 of shear spring 74 a are compressed. As shown and described herein, the V-shaped surface of the shear spring 72 contacts a corresponding V-shaped side wall 190 during compression, wherein the surfaces are preferably shown to be linear and in contact along nearly the entire surface of the shear spring. It will be noted that it is not necessary, although desirable, that the entire V-shaped surface of the shear spring 72 is in contact with the V-shaped wall 190 during compression. Moreover, it is possible that one or both of the contacting surfaces could be curvilinear provided that the surfaces provide a wedging action that serves to compress the shear spring 72. For example, the surfaces of the V-shaped wall 190 and the shear spring 72 do not necessarily need to be linear as shown in the above Figures, although linear surfaces are preferred.

As shown in FIG. 21 b, the elastomeric sections 306 and 308 of shear spring 72 are compressed such that the distance between V-shaped plate 310 and intermediate plate 312 (denoted as A′) is less than distance A shown in FIG. 21 a, and the distance between intermediate plate 312 and base plate 302 (denoted as B′) is less than distance B shown in FIG. 21 a. Similarly, the elastomeric sections 306 and 308 of shear spring 74 a are compressed such that the distance between V-shaped plate 310 and intermediate plate 312 (denoted as C′) is less than distance C shown in FIG. 21 a, and the distance between intermediate plate 312 and base plate 302 (denoted as D′) is less than distance D shown in FIG. 21 a.

Thus, with reference to FIGS. 2 and 3, vehicle suspension 50 may be assembled by using a method including the steps of (i) providing a frame attachment portion 58 adapted for connection to a vehicle frame rail having a spring module 70 attached to the frame attachment portion 58 wherein the spring module 70 has an opening 64 defined by a top wall 84, a bottom wall 86, and first and second side walls 80, 82 of the spring module, (ii) positioning a first part 66 b of a first spring mount 66 within the opening 64, (iii) positioning a first shear spring 72 between a first tapered surface of the first spring mount 66 and a first side wall 80 of the opening 64 of the first spring module 70, (iv) positioning a second shear spring 74 a between a second tapered surface of the first spring mount 66 and second side wall 82 of the opening 64 of the first spring module 70, (v) positioning a second part of the first spring mount 66 within the opening 64, (vi) placing a first threaded connecting rod 164 through a through-hole in at least one of the first part of the first spring mount 66 or the second part of the first spring mount 66, and (vii) tightening the first threaded connecting rod 164 to draw together the first part of the first spring mount 66 and the second part of the first spring mount 66, and to compress the first shear spring 72 between the first side wall 190 of the first spring mount 66 and the first side wall 80 of the opening 64 of the first spring module 70, and also to compress the second shear spring 74 a between the second side wall 190 b of the first spring mount 66 and the second side wall 82 of the opening 64 of the first spring module 70.

In this method of assembling a vehicle suspension, the need for separate spring mounts is eliminated. In addition, other prior art systems required the use of a funnel and difficult compression techniques of the shear spring to position the spring mount and one or more shear spring properly within the vehicle suspension. However, with this method, these problems have been eliminated because the shear springs are compressed by the wedging action of the V-shaped surfaces of the side walls of the spring mount and corresponding V-shaped side walls on the shear springs. The V-shaped surface of the spring mount side walls is formed by tightening the nut onto the connecting rod that passes through the inboard and outboard parts of the spring mount.

In addition, the disclosed vehicle suspension construction also provides significant advantages for servicing and disassembling the vehicle suspensions. For example, if a shear spring needs to be replaced, the serviceman can gradually decompress the shear spring (e.g., reduce the compressive forces acting on the shear springs) within the vehicle suspension by loosening the nuts or connecting rods that were used do draw spring mount portions together to form a spring mount, in a staged and staggered method. The following examples of staged and staggered shear spring decompression methods are applicable to vehicle suspension 50 using two connecting rods 146 and 146 a.

First example of staged and staggered method to decompress shear springs:

Step A1—Turn connecting rod 146 or nut 214 X number of degrees in a direction that causes nut 214 to move away from end 212.

Step A2—Turn connecting rod 146 a or nut 214 a X number of degrees in a direction that causes nut 214 a to move away from end 212 a.

Step A3—Repeat steps A1 and A2 until the shear springs retained by saddle assembly 90 are decompressed.

Second example of staged and staggered method to decompress shear springs:

Step B1—Turn connecting rod 146 or nut 214 X number of degrees in a direction that causes nut 214 to move away from end 212.

Step B2—Turn connecting rod 146 a or nut 214 a (X times 2) number of degrees in a direction that causes nut 214 a to move away from end 212 a.

Step B3—Turn connecting rod 146 or nut 214 (X times 2) number of degrees in a direction that causes nut 214 to move away from end 212.

Step B4—Repeat steps B2 and B3 until the shear springs retained by saddle assembly 90 are decompressed.

In the foregoing examples, X may equal 360° or some other number of degrees. Other examples of staged and staggered method to decompress shear springs are also possible. Prior art systems posed more challenges because there was not a simple way to slowly ease the compressive forces on the shear springs when removing them from the vehicle suspensions.

Staged and staggered methods may also be used to place shear spring in compression. The following examples of staged and staggered shear spring compression methods are applicable to vehicle suspension 50 using two connecting rods 146 and 146 a.

First example of staged and staggered method to compress shear springs:

Step C1—Turn connecting rod 146 or nut 214 X number of degrees in a direction that causes nut 214 to move towards end 212.

Step C2—Turn connecting rod 146 a or nut 214 a X number of degrees in a direction that causes nut 214 a to move towards end 212 a.

Step C3—Repeat steps C1 and C2 until the shear springs retained by saddle assembly 90 are compressed as desired.

Second example of staged and staggered method to compress shear springs:

Step D1—Turn connecting rod 146 or nut 214 X number of degrees in a direction that causes nut 214 to move towards end 212.

Step D2—Turn connecting rod 146 a or nut 214 a (X times 2) number of degrees in a direction that causes nut 214 a to move towards end 212 a.

Step D3—Turn connecting rod 146 or nut 214 (X times 2) number of degrees in a direction that causes nut 214 to move towards end 212.

Step D4—Repeat steps D2 and D3 until the shear springs retained by saddle assembly 90 are compressed as desired.

In the foregoing examples, X may equal 360° or some other number of degrees. Other examples of staged and staggered method to compress shear springs are also possible.

In the example embodiments described herein, threaded connecting rods 146 and 146 a may be arranged in any one of a variety of configuration. Preferably, the connecting rods are M−20×1.5, class 10.9, bolts with sufficient threads to allow for each bolt to pass through both the inboard and outboard saddles and to engage corresponding nuts when the shear springs to be compressed via tightening of the bolts are in an uncompressed state. A shank of each bolt may, for example, be threaded from the bolt head to the shank end opposite the bolt head. Alternatively, each connecting rod could, for example, comprise a different type of bolt, or a screw, or some other suitable fastener. For instance, each connecting rod could be a rod with two threaded ends or a rod threaded from end to end. In this regard, inboard and outboard parts of the saddle could be drawn together to compress a set of shear springs by installing the threaded connecting rod into a hole tapped into one of the inboard and outboard parts of the saddle and using a nut on the opposite end of the connecting rod, or by using a respective nut threaded onto opposite ends of the threaded connecting rod. Also, each connecting rod could itself be round, square, or of some other geometric shape.

FIG. 22 is a view of the outboard side of vehicle suspension 50 having a line 23-23 extending through shear spring 74 a, first side wall 80 a of the second opening 64 a, and V-shaped side wall 190 a of spring mount 66 a.

FIG. 23 is a cross sectional top view of vehicle suspension 50 along line 23-23 shown in FIG. 22. In particular, shear spring 74 a is shown in compression between side wall 80 a and V-shaped side wall 190 a of the second spring mount 66 a. The V-shaped wall 310 a of shear spring 74 a is in contact with V-shaped side wall 190 a and shear spring 74 a is wedged against side wall 80 a. Base plate 302 of shear spring 74 abuts side wall 80 a. Frictional forces acting on shear spring 74 a, side wall 80 a, and V-shaped side wall 190 a provide a primary means to prevent lateral movement of shear spring 74 a. Base plate 302 includes flange 304 that extends from an end of base plate 302 in a direction away from the V-shaped plate 310. Similarly flange 305 extends from another end of base plate 302 in a direction away from V-shaped plate 310. In this manner, flanges 304 and 305 and side wall 80 a can secondarily restrict lateral movement of the shear spring 74. For example, side wall 112 c can restrict lateral movement of shear spring 74 when flange 304 is in contact with side wall 112 c, and side wall 110 c can restrict lateral movement of shear spring 74 in an opposite direction when flange 305 is in contact with side wall 110 c.

FIG. 24 is a bottom view of vehicle suspension 50 shown in FIGS. 2 and 3, where the flanges 304 and 305 of the shear springs are shown extending beyond the spring modules that comprise those shear springs. In particular, flanges 304 and 305 of shear spring 74 a are shown as extending beyond side edges 110 c and 112 c of side wall 82 a, and flanges 304 and 305 of shear spring 72 are shown as extending beyond side edges 110 and 112 of side wall 80.

FIGS. 25 a and 25 b are elevational views of vehicle suspension 50 shown in FIGS. 2 and 3.

FIG. 26 illustrates an alternate embodiment showing vehicle suspension 450 having a frame attachment portion 458 attached to spring module 470, and having a single opening 464 defined by top wall 470 a, side walls 470 b and 470 c, and bottom wall 470 d. Shown positioned within opening 464 are first shear spring 72, second shear spring 74, and load cushion 76 which are the same as the shear springs and load cushion described in FIGS. 1-25 above. Also shown is spring mount 466 which includes separate inboard and outboard spring mount portions. A connecting rod 465 is used to draw the inboard and outboard spring mount portions of spring mount 466 together and to compress shear springs 72 and 74 between spring mount 466 and side walls 470 c and 470 b, respectively, of spring module 470. Drawing the inboard and outboard spring mount portions form V-shaped walls that abut the V-shaped walls of shear springs 72 and 74.

FIG. 27 illustrates a vehicle suspension 650 comprising a pair of frame attachment portions 451 and 452 that are attached to each other via a saddle 480. Frame attachment portions 451 and 452 include spring modules 453 and 455, respectively.

Spring module 453 includes a pair of shear springs 300 (as described above) that are retained in compression between opposing side walls of spring module 453 and a spring mount 459. Spring module 453 further includes a load cushion 454 that may be configured like any of load cushions 400, 400 a, and 400 b shown in one or more of FIGS. 14-20. Spring mount 459 may be configured like spring mount 766, described below with respect to FIG. 29, in that spring mount 459 may include a mounting bracket similar to mounting bracket 770 of spring mount 766. A threaded connecting rod 146 e and nut 457 may be used to attach saddle 480 to the mounting bracket of spring mount 459.

Similarly, spring module 455 includes a pair of shear springs 300 (as described above) that are retained in compression between opposing side walls of spring module 455 and a spring mount 460. Spring module 455 further includes a load cushion 456 that may be configured like any of load cushions 400, 400 a, and 400 b shown in one or more of FIGS. 14-20. Spring mount 460 may be configured like spring mount 766, described below with respect to FIG. 29, in that spring mount 460 may include a mounting bracket similar to the mounting bracket 770 of spring mount 766. A threaded connecting rod 146 f and nut 458 may be used to attach saddle 480 to the mounting bracket of spring mount 460.

FIG. 28 illustrates an alternate vehicle suspension 550 having frame rail attachment portion 558 attached to first spring module 70 and second spring module 70 a having shear springs, spring mounts and load cushions constructed in the same manner as described above with respect to FIGS. 1-25. Vehicle suspension 550 further includes a third spring module 570 adjacent to the second spring module 70 a, wherein the shear springs, load cushion, and spring mount with spring module 570 are also constructed in the same manner as described above with respect to FIGS. 1-25.

Vehicle suspension 550 further includes a saddle assembly 571 comprising two separate saddles connected by connecting rods 146 b, 146 c, and 146 d. Saddle assembly 571 includes six V-shaped walls for compressing each of one of the six shear springs contained within vehicle suspension 550 as those V-shaped walls are formed by tightening nuts onto connecting rods 146 b, 146 c, and 146 d. Loosening the nuts on those connecting rods, preferably in a staged and staggered manner, allows for removing the compressive forces placed on the six shear springs contained within vehicle suspension 550.

FIG. 29 illustrates a spring mount 766 having a through-hole 205, a load cushion mounting surface 767, and V-shaped walls 768 and 769. Spring mount 766 is a spring mount that is not integrally connected to a saddle as is the case with spring mount 66 shown in FIGS. 1-25. However, spring mount 766 does use a connecting rod to draw together an inboard part and an outboard part of the spring mount in the same manner as shown in one or more of FIGS. 1-25 and described above. Spring mount 766 may be used in connection with the shear springs and load cushion shown in one or more of FIGS. 1-25 and described above. However, spring mount 766 is instead attached to a saddle using mounting bracket 770. Thus, as is known in the art, the spring mount 766 may be attached to a saddle, for example, in the manner described in U.S. Pat. No. 7,926,836.

FIG. 30 illustrates vehicle suspension 850. Vehicle suspension 850 comprises a saddle assembly similar to the saddle assembly 90 of vehicle suspension 50, shear springs similar to the shear spring 300 described above, and load cushions similar to any of the load cushions 400, 400 a, and 400 b described above. Vehicle suspension 850 has some notable differences when compared to vehicle suspension 50. Those differences include: (i) frame rail attachment portions 858 and 858 a have geometries that differ from the geometries of frame rail attachment portions 58 and 58 a, (ii) the set of gussets including gussets 854 a, 854 b, 854 c, 854 d, 854 e, 854 f, 854 g, and 854 h have geometries that differ from the geometries of set of gussets including gussets 62 a, 62 b, 62 c, 62 d, 62 e, and 62 f, and (iii) vehicle suspension 850 includes frame hanger attachment portion strengtheners, such as strengtheners 856 a and 856 b, on an inboard side of its frame rail attachment portions.

Furthermore, a filler plate 883 is attached between adjacent spring modules 70 b and 70 c of vehicle suspension 850, and a filler plate 884 is attached between spring modules 70 d and 70 e of vehicle suspension 850. Each side wall of a lower U-plate that is adjacent to filler plates 883 or 884 and that forms a part of an opening of spring modules 70 b, 70 c, 70 d, or 70 e may include 2 weld-slots through which weld beads for welding that side wall to the adjacent filler plate. Each of those weld-slots may have the size and shape of weld-slot 81 described above.

Frame hanger attachment portion strengtheners are typically used in embodiments in which the distances between the tops of the spring module (e.g., tops 855, 855 a) and the top edge of the frame attachment portions (e.g., edges 857), and the distance between spring module tops 855 c, 855 d and the top edge 857 a, exceed a given threshold distance.

In FIG. 30, the top edges 857 and 857 a are straight, and walking beam ends 859 and 859 a are identified. In accordance with a first embodiment in which vehicle suspension 850 is installed in a vehicle, walking beam end 859 is closer to a front end of the vehicle than walking beam end 859 a. In accordance with a second embodiment in which vehicle suspension 850 is installed in a vehicle, walking beam end 859 a is closer to the front end of the vehicle than walking beam end 859.

FIG. 31 illustrates vehicle suspension 860, which is the same as vehicle suspension 850 shown in FIG. 30, except that frame rail attachment portions 868 and 868 a have geometries that differ from the geometries of frame rail attachment portions 858 and 858 a. Those geometries may differ, at least in part, because the geometries have different patterns and/or quantities of frame rail attachment holes between the frame hanger attachment portion strengtheners and the top edges of the frame hanger attachment portions.

In FIG. 31, the top edges 867 and 867 a are straight, and walking beam ends 859 and 859 a are identified. In accordance with a first embodiment in which vehicle suspension 860 is part of a vehicle, walking beam end 859 is closer to a front end of the vehicle than walking beam end 859 a. In accordance with a second embodiment in which vehicle suspension 860 is part of a vehicle, walking beam end 859 a is closer to the front end of the vehicle than walking beam end 859.

The walking beams used with the various example vehicle suspensions described herein may be constructed in any of a variety of arrangements. In that regard, the number of and/or dimensions of various plates used to construct the walking beams may vary between the various walking beam arrangements. Furthermore, the walking beams attached to the each vehicle suspension may be retained to the vehicle suspension via various components such as, for example, a set of components comprising a saddle cap and threaded connecting rods or a set of components comprising a U-bolt and a pair of nuts.

Example embodiments of the present invention have been described above. Those skilled in the art will understand that changes and modifications may be made to the described embodiments without departing from the true scope and spirit of the present invention, which is defined by the claims. 

1. A shear spring comprising a base and a V-shaped surface opposite the base adapted to mate with a corresponding V-shaped surface positioned on a side wall of a spring mount, and an elastomeric material positioned between the base and the V-shaped surface, wherein the base includes a first flange extending away from the V-shaped surface and adapted to be positioned outwardly from a first edge of a side wall of a spring module, and wherein the base includes a second flange extending away from the V-shaped surface and adapted to be positioned outwardly from a second edge of the side wall of the spring module, where the first flange and the second flange are positioned in parallel planes.
 2. The shear spring of claim 1, further comprising: one or more intermediate plates positioned between the base and the V-shaped surface, wherein at least one of the intermediate plates is V-shaped or flat.
 3. The shear spring of claim 1, wherein the base comprises a flat plate and the first flange and the second flange extend perpendicularly from the base plate.
 4. The shear spring of claim 1, wherein the base has a truncated U-shape cross section.
 5. The shear spring of claim 1, wherein the base and the first flange and the second flange are formed from a single plate.
 6. The shear spring of claim 5, wherein the V-shaped surface comprises a V-shaped plate.
 7. The shear spring of claim 5, wherein the base plate is V-shaped.
 8. The shear spring of claim 1, wherein the first flange and the second flange are adapted to extend beyond first and second sides of a side wall of a spring module opening so as to restrict lateral movement of the shear spring with respect to the side wall of the spring module opening.
 9. The shear spring of claim 1, further comprising an intermediate plate positioned between the base and the V-shaped surface.
 10. The shear spring of claim 9, wherein the base comprises a base plate.
 11. The shear spring of claim 10, wherein the V-shaped surface comprises a V-shaped plate.
 12. The shear spring of claim 11, wherein the intermediate plate is V-shaped.
 13. The shear spring of claim 1, wherein the shear spring has a free-state vertical offset between the V-shaped surface and the base equal to one half of the vertical compression of the shear spring.
 14. A shear spring comprising a base plate and a V-shaped surface opposite the base plate adapted to mate with a corresponding V-shaped surface positioned on a side wall of a spring mount, and an elastomeric material positioned between the base plate and the V-shaped surface; wherein the shear spring has a free-state vertical offset between the V-shaped surface and the base plate, wherein the base plate includes a first flange extending away from the V-shaped surface and adapted to be positioned outwardly from a first edge of a side wall of a spring module, and wherein the base plate includes a second flange extending away from the V-shaped surface and adapted to be positioned outwardly from a second edge of the side wall of the spring module, where the first flange and the second flange are positioned in parallel planes.
 15. The shear spring of claim 14, wherein the base plate comprises a flat plate and the first flange and the second flange extend perpendicularly from the base plate.
 16. The shear spring of claim 14, wherein the base plate has a truncated U-shape cross section.
 17. The shear spring of claim 14, wherein the base plate and the first flange and the second flange are formed from a single plate.
 18. The shear spring of claim 14, wherein the first flange and the second flange are adapted to extend beyond first and second sides of a side wall of a spring module opening so as to restrict lateral movement of the shear spring with respect to the side wall of the spring module opening.
 19. A shear spring comprising a base plate and a V-shaped surface opposite the base plate adapted to mate with a corresponding V-shaped surface positioned on a side wall of a spring mount, and an elastomeric material positioned between the base plate and the V-shaped surface; wherein the shear spring has a free-state vertical offset between the V-shaped surface and the base plate, wherein the free-state vertical offset is equal to half the vertical compression of the shear spring. 